Pressure-gage.



UNITED STATES Patentedlv January 17, 1905.

PATENT' 'OFFICE PRESSURE-GAGE.

SREOIFICATION forming' part of Letters Patent No. 780,095, dated January 17,'Y 14905.-

Applioaticn liled June 26d, 1903. Serial No. 163,189.

'To all whom it'maly concern: y

Be it known that I, MAX GEHRE, residing at Rath., near Dsseldorf, Germany, have invented certain new and useful Improvements L inPressure-Gages, of which the following is l, a specification.

. In vorder to measure accurately the fluctuations in pressure of a pressure medium within a pipefsystem or the like, according to a wellyknown',process, these fluctuations are meas- 'n'red at aplace where the cross-section is nar- "jignd Eig. 3 shows a detail.

rowed on purpose;

In'the accompanying drawings, Figure l is av sectional view of a measuring. apparatus. Fig. 2 is a sectional plan of lAs'illustrated in Fig. 1 of the accompany- L ing? drawings, a reduction-piece w is inserted between the-plpes le' k2, and tubes d and c iQlljarefbranched 0H before and behind said piece.

fqZEhese tubes lead to vesselsff and f', respecwhich are connected with the proper tively. measuring "spectively, .53 5

The measuring vessel is'cylindrical, and its bottom is largely bent upward. The circular space o, Figs. 1 and 3, contains quicks'ilver, in which the bell-shaped piston c is immersed. Thus two chambers a, and are formed, which are under the same presjsures as-the pipes lc' and k,respectively. It' thel pressures in a and b are equal, the level of the I "quicksilver is, for instance, at 1, lwhile for the `greatest difference of pressure the Quicksilver stands in the chamber a at the level 3 and in the'chamber b at the'A level 2. Without special arrangements it might happen in certain cases that the pressure in a became suddenly very high. The lquicksilver l forced into l2', or even into the tubes under vthe j this, a valve fu. is

lower edge of the bell., and the apparatus would indicate incorrectly. In order t0 avoid arranged 'in such a manner that the tube e is closed when the bell reaches the position which corresponds to the greatest allowable difference of pressure. This arrangement has further for its object to guide gie piston-rod e' `with the least possible fric- If the chamber b contains a gas, such as air,

part-of Fig. l,`

'device by the tubes d and e, re-I would then be the Quicksilver when the pressure'increases suddenly, as described before, may be dis- `|persed, and thus oxidized and wasted.' In

Z is preferably tilled with a liquid which is lighter than quicksilverwfor instance, with water. This liquid further fillsthe tube -e and stands in the chamber a at sucha level because the pressures in w. and b equalize each other immediately.

When the bell c moves up and down, the column of liquid Ais naturally moved to and fro, so that the level of the liquid in d and e rises and falls, especiallyif said tubes d and e are rather narrow. cause a considerable and undesirable difierence 'of pressure between a andY b, whereby the working of the apparatus wouldl be completely disturbed. In order to avoid this drawback, the enlargements f and f' are provided in the tubes ci d reduction-piece w and the measuring appara- 'tus. The surface of the liquid in these en largements is very great in comparison with thel diameter of the tubes al e. Therefore the level of the liquid will rise and fall only to lsuch a small extent that any essential influence -upon thejc'orrect Working of the apparatus `is impossible. Tubes s are 4provided as overflows in the vessels f and f', which are preferably made in one, as shown. The inserted liquid', preferably water, further keeps facilitates the`handling of the' same. What I claim,- and desire tosecure by Letters Patent of the United States, iS`- as 7c. and 7c, separated by a restricted' orifice., two reservoirs, as f and f', connected respectlvely with said tubes or chambers andan indicating device 4consisting of aL cylinder havorder to prevent this draw bacln'the lchamber This circumstance might the apparatuscool, which generally is impos-` sible n other similar devices, and thus greatly The combination oi' two tubes er chambers,

that the eiiects of the tlwof columns of liquid the quicksilver prevents the latter from rising,

and e e' between.the

ing an upwardly-extendingA b ottom forming ing two bodiesrpfliquids of different specific 1 an annu'larspace, a bell in "said cylinder-nud gravity, for thgpurpose set forth.

occupying said annular space and two tubesh In testimonyfwhereof I have hereunto set one extending from one of sind frelerolllrs t my hand in the presence of two Witnesses. 5 the cylinder at a point outsi e o t e e an f 1 s the other extending,r from the other reservoir MAX GEI-IRL' to the cylinder at a point inside of the bell, a Witnesses: Y valve controlling' the latter tube and itself WILLIAM ESSENWEIN, s

controlled by said bell, said cylinder Ycoi'itainl* PETEBVLIEBER.

It is hereby certified that in Letters Patent No. 780,095, granted January 17, 1905, upon the application of Max Gehre, vof Rath, near Dsseldorf, Germany, an error appears requiring the following correction: In figure 1, ofthe drawings forming a partl of said patent; the chambers f and f 1 were kimproperly changed by the oice in applying an-amendment filed by the patentee before the issue of the patent, to represent them as entirely filled with water; whereas' the shade 'lines in the upper portion of said chambers above the centralhorizontal line should have been omitted to show the lower half only of said chambers filled with water; and that the said Letters Patent should be read with this 'correction therein that the same mayleonform tothe record of the vcase in the Patent Oce. Y v l I Signed and sealed this 27th day of June, A. D., 1905.

[SEAL] Y F. I. ALLEN,

Commissioner of Patents.

Cour'ection in Letters Patent No. 780,095.

ing an upwardly-extendingA b ottom forming ing two bodiesrpfliquids of different specific 1 an annu'larspace, a bell in "said cylinder-nud gravity, for thgpurpose set forth.

occupying said annular space and two tubesh In testimonyfwhereof I have hereunto set one extending from one of sind frelerolllrs t my hand in the presence of two Witnesses. 5 the cylinder at a point outsi e o t e e an f 1 s the other extending,r from the other reservoir MAX GEI-IRL' to the cylinder at a point inside of the bell, a Witnesses: Y valve controlling' the latter tube and itself WILLIAM ESSENWEIN, s

controlled by said bell, said cylinder Ycoi'itainl* PETEBVLIEBER.

It is hereby certified that in Letters Patent No. 780,095, granted January 17, 1905, upon the application of Max Gehre, vof Rath, near Dsseldorf, Germany, an error appears requiring the following correction: In figure 1, ofthe drawings forming a partl of said patent; the chambers f and f 1 were kimproperly changed by the oice in applying an-amendment filed by the patentee before the issue of the patent, to represent them as entirely filled with water; whereas' the shade 'lines in the upper portion of said chambers above the centralhorizontal line should have been omitted to show the lower half only of said chambers filled with water; and that the said Letters Patent should be read with this 'correction therein that the same mayleonform tothe record of the vcase in the Patent Oce. Y v l I Signed and sealed this 27th day of June, A. D., 1905.

[SEAL] Y F. I. ALLEN,

Commissioner of Patents.

Cour'ection in Letters Patent No. 780,095.

It is hereby certified that in Letters Patent No. 780,095, granted January 17, 1905, upon the application of Max Gehre, of Rath, near Dsseldorf, Germany, an error appears requiring the following correction: In figure 1, of the drawings forming a. part of said patent,- the chambers fand fl were improperly changed hy the office in applying an-amendment led by the patentee before the issue of the patent, to represent them as entirely filled with water; whereas the shade lines in the upper portion of said chambers above the central horizontal line should have heen omitted to show the lower half only of said chambers filled with water; and that the seid Letters Patent should he read with this correction therein that the same may conform to the record of the case in the Patent Oce.

Signed and sealed this 27th day of June, A. D., 1905.

[SEAL] F. I. ALLEN,

Commissioner of Patents. 

